Hello and welcome to another issue of This Week in Rust! Rust is a programming language empowering everyone to build reliable and efficient software. This is a weekly summary of its progress and community. Want something mentioned? Tag us at @ThisWeekInRust on Twitter or @ThisWeekinRust on mastodon.social, or send us a pull request. Want to get involved? We love contributions.

This Week in Rust is openly developed on GitHub and archives can be viewed at this-week-in-rust.org. If you find any errors in this week's issue, please submit a PR.

Updates from Rust Community



Project/Tooling Updates


Rust Walkthroughs


Crate of the Week

This week's crate is rouille, a small synchronous web framework.

Thanks to Peter Puetz for the suggestion!

Please submit your suggestions and votes for next week!

Call for Participation; projects and speakers

CFP - Projects

Always wanted to contribute to open-source projects but did not know where to start? Every week we highlight some tasks from the Rust community for you to pick and get started!

Some of these tasks may also have mentors available, visit the task page for more information.

If you are a Rust project owner and are looking for contributors, please submit tasks here.

CFP - Speakers

Are you a new or experienced speaker looking for a place to share something cool? This section highlights events that are being planned and are accepting submissions to join their event as a speaker.

  • No new calls for speakers this week

If you are an event organizer hoping to expand the reach of your event, please submit a link to the submission website either through a PR to TWiR or on the [Rust-lang forums].[link TBD]

Updates from the Rust Project

268 pull requests were merged in the last week

Rust Compiler Performance Triage

Some of the recent noise swings have been appearing again this week, but luckily less often than before. There were a few actual regressions, but most of them were localized to a single stress test. On the other hand, there were a few very nice wins across the board, especially for check and incremental builds, primarily thanks to #118824 and #119265.

Triage done by @kobzol. Revision range: bf9229a2e366b4c311f059014a4aa08af16de5d8..1ab783112ab4e4807304dbd249b39771246013ef


(instructions:u) mean range count
Regressions ❌
0.6% [0.6%, 0.6%] 1
Regressions ❌
2.5% [0.3%, 4.2%] 10
Improvements ✅
-0.8% [-3.3%, -0.1%] 180
Improvements ✅
-1.2% [-5.5%, -0.2%] 109
All ❌✅ (primary) -0.8% [-3.3%, 0.6%] 181

5 Regressions, 7 Improvements, 2 Mixed; 1 of them in rollups 58 artifact comparisons made in total

Full report here

Approved RFCs

Changes to Rust follow the Rust RFC (request for comments) process. These are the RFCs that were approved for implementation this week:

  • No RFCs were approved this week.

Final Comment Period

Every week, the team announces the 'final comment period' for RFCs and key PRs which are reaching a decision. Express your opinions now.


  • No RFCs entered Final Comment Period this week.

Tracking Issues & PRs

Language Reference

  • No Language Reference RFCs entered Final Comment Period this week.

Unsafe Code Guidelines

  • No Unsafe Code Guideline RFCs entered Final Comment Period this week.

New and Updated RFCs

Call for Testing

An important step for RFC implementation is for people to experiment with the implementation and give feedback, especially before stabilization. The following RFCs would benefit from user testing before moving forward:

  • No RFCs issued a call for testing this week.

If you are a feature implementer and would like your RFC to appear on the above list, add the new call-for-testing label to your RFC along with a comment providing testing instructions and/or guidance on which aspect(s) of the feature need testing.

Upcoming Events

Rusty Events between 2023-12-27 - 2024-01-24 🦀



North America

If you are running a Rust event please add it to the calendar to get it mentioned here. Please remember to add a link to the event too. Email the Rust Community Team for access.


Please see the latest Who's Hiring thread on r/rust

Quote of the Week

Rust can be rather more verbose than C; there are a lot of invariants that have to be expressed in the code. But that is countered by the need for far less error-handling code; it turns out to be a wash, with the size of the two implementations being about the same.

Alice Ryhl at the Linux Plumbers Conference as quoted by Jonathan Corbet, LWN

Thanks to Ivan Fraixedes for the suggestion!

Please submit quotes and vote for next week!

This Week in Rust is edited by: nellshamrell, llogiq, cdmistman, ericseppanen, extrawurst, andrewpollack, U007D, kolharsam, joelmarcey, mariannegoldin, bennyvasquez.

Email list hosting is sponsored by The Rust Foundation

Discuss on r/rust